The present disclosure relates to control devices that control a vehicle drive device in which an engagement device, a rotating electrical machine, and a speed change device are arranged in this order from the internal combustion engine side on a power transmission path connecting the internal combustion engine and wheels.
A control device described in Japanese Patent Application Publication No. 2012-121568 (JP 2012-121568 A) is known as such a control device. Japanese Patent Application Publication No. 2012-121568 describes a technique of reducing shock that is caused when start control to start an internal combustion engine with output torque of a rotating electrical machine is performed in an electric drive state where a vehicle is moved with output torque of the rotating electrical machine with an engagement device being disengaged. Specifically, Japanese Patent Application Publication No. 2012-121568 describes that a shift engagement device of the speed change device which has been engaged to establish a shift speed is controlled to a slip engaged state during the control to start the internal combustion engine, whereby this shift engagement device absorbs variation in torque which is caused by starting of the internal combustion engine. Japanese Patent Application Publication No. 2012-121568 describes that, if a downshift of the speed change device is requested when starting the internal combustion engine, a shift engagement device to be disengaged by the downshift is selected as a shift engagement device to be controlled to a slip engaged state in order to absorb the variation in torque.